Yuh Tzean, Ho-Hsiung Chang, Tsui-Chin Tu, Bo-Han Hou, Ho-Ming Chen, Yi-Shu Chiu, Wei-Yi Chou, Li Chang, and Hsin-Hung Yeh* (2020) Engineering Plant Resistance to Tomato Yellow Leaf Curl Thailand Virus Using a Phloem-Specific Promoter Expressing Hairpin RNA https://apsjournals.apsnet.org/doi/10.1094/MPMI-06-19-0158-R (Selected for publication in MPMI Focus Issue on Cell Biology of Virus-Plant and Virus-Vector Interaction and commentary in the same issue).
Transgenic approaches employing RNA interference (RNAi) strategies have been successfully applied to generate desired traits in plants; however, variations between RNAi transgenic siblings and the ability to quickly apply RNAi resistance to diverse cultivars remain challenging. In this study, we assessed the promoter activity of a cauliflower mosaic virus 35S promoter (35S) and a phloem-specific promoter derived from rice tungro bacilliform virus (RTBV) and their efficacy to drive RNAi against the endogenous glutamate-1-semialdehyde aminotransferase gene (GSA) that acts as a RNAi marker, through chlorophyll synthesis inhibition, and against tomato yellow leaf curl Thailand virus (TYLCTHV), a begomovirus (family Geminiviridae) reported to be the prevalent cause of tomato yellow leaf curl disease (TYLCD) in Taiwan. Transgenic Nicotiana benthamiana expressing hairpin RNA of GSA driven by either the 35S or RTBV promoter revealed that RTBV::hpGSA induced stronger silencing along the vein and more uniformed silencing phenotype among its siblings than 35S::hpGSA. Analysis of transgenic N. benthamiana, 35S::hpTYLCTHV, and RTBV::hpTYLCTHV revealed that, although 35S::hpTYLCTHV generated a higher abundance of small RNA than RTBV::hpTYLCTHV, RTBV::hpTYLCTHV transgenic plants conferred better TYLCTHV resistance than 35S::hpTYLCTHV. Grafting of wild-type (WT) scions to TYLCTHV RNAi rootstocks allowed transferable TYLCTHV resistance to the scion. A TYLCTHV-inoculation assay showed that noninfected WT scions were only observed when grafted to RTBV::hpTYLCTHV rootstocks but not 35S::hpTYLCTHV nor WT rootstocks. Together, our findings demonstrate an approach that may be widely applied to efficiently confer TYLCD resistance.
2020/04/13 11:00 AM
Dr. Julian Schroeder (Novartis Distinguished Professor in Plant Sciences, University of California, San Diego, USA)
CO2 Sensing in Plants and New Insights into Drought-Induced Abscisic Acid Signal Transduction
Auditorium A134, Agricultural Technology Building 2020/09/07 10:00 AM
Dr. Michael Alan Huffman (Associate Professor (tenured), Department of Ecology and Social Behavior, Primate Research Institute, Kyoto University, Japan)
Learn from primate self-medication about the maintenance of human and domestic animal health?
Auditorium A134, Agricultural Technology Building